Braking device for motor vehicle transmissions



K. MAYBACH March 11, 1941.

BRAKING DEVICE FOR MOTOR VEHICLE TRANSMISSIONS Filed April 4, 1938 w w n m M wm m m F0 Patented Mar. 1 1,

UNITED STATES BRAKING DEVICE FOR. MOTOR vsmom TRANSMISSIONS Karl Maybach, vFriedrichshaten, Bodensee, Germany, assignor to Maybach-Motorenbau G. in. b. H., Friedrichshafen, Bodensee, Germany Application April 4, 1938, Serial No. 200,001 In Germany May 3, 1937 16 Claims.

This invention relates to a braking device such as may be employed for automobile transmissions, to shorten the gear shiftingperiod by slowing down the faster rotating of two parts of a transmission which are to be shifted into driving relation, and thereby quickly bringing said parts to substantially the same relative speed and permitting their engagement.

A primary object of the invention is to provide a braking device which will insure uniform engagement of various areas of the coactlng braking surfaces, and to this end to provide a compensating mechanism which will automatically adjust itself under all conditions to equalize the braking forces applied to the brake parts.

A further object of the invention is to provide a braking device'employing a novel type of actuating mechanism which is of extremely com pact construction. The same readily lends itself to automobile transmissions which ordinarily are so arranged that only very limited space is available. The arrangement is such that the meeting braking parts may be placed in the transmission housing and the actuating mechanism 10- 5 sated outside. preferably in a. small auxiliary casing, and operated through the wall of the housing.

Another object of the invention is to provide a braking device incorporating transmitting 6 means for distributing braking forces originating at a common source to a plurality of points of the coacting braking parts. and in which means the several forces react against and equalize each other in dependency on the conditions emsting at difierent areas of the braking surfaces so that the eifective braking pressure is the same at the several points of application.

In the accompanying drawing, Fig. 1 is a more or less diagrammatic view largely in section of so an exemplary embodiment of the invention; Fig. 2 is a sectional view taken on line 11-11 of Fig. i; and, Fig. 3 is a similar sectional view taken on line IIIIII of Fig. 1.

The fragmentary casing portion i indicates so one end of an illustrative automobile transmission housing. The gear 2 and its rotary supporting shaft represent the parts to be slowed down during shifting incident to bringing about driving engagement with another part (not shown) 50 of the transmission.

The braking parts in the present construction are located inside the housing portion 5. One of such parts is provided by the inner peripheral surface 3 of the gear 2. A brake shoe 6 coactive @5 therewith is carried by a supporting member 5,

preferably a metal ring, which is fixed against rotation but movable axially to engage the shoe with the rotating gear surface 3.

The braking pressure is transmitted to ring 5 through pins 6 slidably mounted in the end Wall 5 of the housing by means of an external rotary actuating sleeve]. Such sleeve as shown extends at right angles to,-and diametrically of, the gear shaft, and the same may be enclosed in a compact auxiliary easing l0 fixed to the end of 10 the transmission housing.

To insure uniform braking pressure and prevent jamming or irregular operation of the coacting braking parts, the rotary sleeve 8 is so mounted and driven that it may tilt relative to 15 the braking parts. The take off of pressure is made from longitudinally spaced points 'on the sleeve and bearing means are provided which permit the shaft to tilt about a point located midway or substantially so between the take oii 26 points. The driving means for rotating the sleeve may take the form of a rigidly mounted rotating member, and in such case a flexible driving connection is employed between such member and ,the sleeve so as not to interfere with tilting move- 2 merit of the latter. in the present instance a single Supporting bearing is employed which engages the rotatable sleeve 8 at its midpoint and acts as a fulcrum between the take oif points, and connection with 30 a rotatable driving shaft is also made at the midpoint. The sleeve is thus supported like a balance beam so that it can tilt as well as rotate.

If due to conditions at the braking surfaces or other causes a greater actuating force tends to develop through one end of the sleeve than the other, the sleeve will swing transversely so that the first end is shifted away from the braking parts until the same effective forces exist at both ends and equilibrium is maintained throughout the length of the sleeve. In this manner it is possible to overcome the dirficulties inherent in an actuating sleeve or shaft which .is rigidly journaled, or one which is journaled at one of its ends and tilts objectionably under the torsicnal efiects incident to rotation, in either-of which cases equalized braking pressure can not be produced in the braking parts at the difierent points of application.

The several features of the sleeve 8 above re- 59 ferred to will be understood from thedrawing. Extending internally of the sleeve is a rotary shaft 8 engaged at one end byspring it and hearing at its other end against packing 52 in casing to. An actuating arm. it, which may be point of the sleeve.

- Fig. 1, for example, a sleeve tab ing element and an v s and serves to rotate the same. smaller diameter than the bore of sleeve] and 'points of brake ring about its longitu transverse axis, and a pair of diametrically op-' oil hrough the gear shitting mechanism, connectswith the extension portion ll of shaft Shaft I is o! is 'splined through suitable teeth to only the mid- Sleeve 8 is iournaled in a single bearing comprising half ring II on the side of casing Iii, suchbearing also being, located atthe midpoint of the sleeve. Thus the sleeve'is free to tilt axially to a limited degree on its bearing-and relative to shaft 8, and can of the shaft.

The transmission of the braking forcev from sleeve 8 to pins 6 is made through suitable pressure applying elements such, for example'as cams I. I equally spaced in opposite directions'irom the midpoint journal and driving connection with shaft 9, being located at or near the ends of sleeve 8. "The'pressure transmitted through the diametrically opposite several pins is'applied to 5. 'Thus if shoe 4 tends to engage the surface of gear 2 with greater force at one point than'another, sleeve will tilt and thus automatically adjust and equalize the forces transmitted through the respective pins 6 so that a uniform braking pressure will be applied at the diametrically opposed areas of the braking surfaces.

As above mentioned, braking ring 5 while axially movable should be fixed against rotation. This can be done in various ways. As shown in IS may be secured in the wall oi'the' housing provided with slots l 'l slidably engaging ribs is formed on the inner periphery of ring 5. or again, ring 5 may be rigidly connected to the ends of pins 6.

I claim: v

1'. A braking device comprising a rotary braking element and an opposing non-rotary braking element, one movable axially into engagement with the other, an actuating member rotatable 'al axis'and tiltable about a posed elements for applying braking pressure to circumferentially spaced points of the opposing braking elements under'rotation or the actuating member operably connectingv with the actuating member at points equally spaced in opposite longitudinal directions. from the tilting axis of the actuating member- 2. A braking device comprising a rotary braking element and an opposing non-rotary braking element, one movable axially into engagement with the other, a rotatableactuating member,-

longitudinally spaced'elements onsaid member for transmitting braking pressure to circumferentially spacedv points of the opposing braking 5 0 elements upon rotation of themember, and

mounting means yieldingly supporting the actu-- ating member for tilting movement'in a plane parallel to the axis or the braking elements about a point midway between the spaced pressure transmitting elements. Z v

3. A braking device comprising a rotary brakaxis,longitudinally spaced elements on said memher for transmitting braking pressure-to diametrically opposite points of the opposing braking elements'upon rotation of the member, and a'bearelement .ment engageable therewith, a rotatable actuatshiit axially.

' merits.

ding element and an ing element, one movable axially into engagement with the other, an actuating member rotatable Suchelements are longitudinally and member tiltable about its midpoint,

- opposing braking opposing non-rotary brak ing element engageable therewith, a diametrically extending actuatingv member rotatable about its 70 midway between the spaced pressure transmitting elements.

4. A braking devicecomprising a rotary braking and an opposing non-rotary brakingeleing-,member, longitudinally spaced elements on said member for transmitting braking pressure to ciroumierentially spaced'ppints of the opposing. braking elements upon rotation of the memher, and a half bearing providing for transverse rocking movement of the rotatable actuating member and engaging. said member at a point midway between the pressure transmitting ele- 5. A braking device comprising a rotary brakopposing non-rotary bratabout "its longitudinal axis and tiltable about a transverse axis in a plane parallel to the axis of the braking elements, longitudinally spaced elements for transmititng braking pressure to circumferentiall-y spaced points of the opposing braking" elements under rotation of the actuating member connecting with the actuating member at points longitudinally spaced in opposite directions from the tilting axis-of said member.

6. A braking device comprising a rotary braking element and an opposing non-rotary braking element engageable therewith, a rotatable actuat ing member tiltable about its longitudinal midpoint, spaced elements engaging the actuating member on opposite sides of the midpoint, operating means for rotating the actuating member and a flexible driving connection between said operating means and the actuating member pro viding for tilting movement of the actuating I member.

7. A braking devicecomp'rising a rotary braking element, an opposing non-rotary braking element movable'axially into engagement therewith, t,

a rotatable actuating member tiltable about its midpoint in a plane parallel to the axis of the braking elements, driving means connecting with the actuating member at its midpoint, and spaced elements for transmitting braking pressure to circumferentially spaced points of the opposing braking elements connecting with the actuating member at points spaced in opposite longitudinal directions from its midpoint.

8. A braking device comprising ing element, ment engagea'ble therewith, a rotatable actuating a rotatable driving shait flexibly connected to the midpoint of the actuating memberior rotating the same, and spaced elements for transmitting braking pressure to circumierentially spaced points of the elements connecting with the opposite ends of the actuating member. I

9. A braking device comprising a rotary braking element, anopposlng non-rotary braking element engageable therewith, arotatable hollow actuating sleeve mounted for tilting movement about its longitudinal midpoint, a rotary driving a rotary brakan opposing non-rotary braking eleshaft extending into the sleeve and connecting ating member, longitudinally spaced elements on.

said member for transmitting braking. pressure to circumierentially spaced points of the opposing braking elements, a driving member connecting with the actuating member midway between the pressure transmitting elements, and molmting means supporting the actuating member for swinging movement at its midpoint about an axis extending transversely of the axis of the braking elements.-

1 11. A braking device comprising a rotary braking element, an opposing non-rotary braking element engageable therewith, a rotatable actuatin member, longitudinally spaced elements on said member for transmitting braking pressure to circumferentially spaced points oi the opposing braking elements, a driving member connectingv with the actuating member midway between the pressure transmitting elements, and a single bearing in which the actuating member is tiltable engaging the actuating member at its point of connection with the driving member.

12; A braking-device comprising a rotary brak ing element, an opposing non-rotary brahng ele- 'ment engageable therewith, a rotatable actuating member, a mounting eng n the longitudinal midpoint of the actuating member, driving means braking elements, a

for rotating the actuating member connecting wlththe midpoint thereof, spaced cams at opmeans supporting said sleeve for tilting movement about its longitudinal midpoint relative to the rotatable driving shaft extending into the sleeve and connecting with the midpoint thereof, and cam means at the opposite ends oi the sleeve for transmitting equalized braking presure to spaced points oi the braking V .14. Abraking device'c'omprising arotary braking member and opposing non-rotary braking means, said parts being movable into'braking engagement one with another, spaced elements for transmitting braking pressure to circumferw entially spaced points of themovable of said.

braking parts,- and an actuating member extending' between the spaced pressure I transmitting elements, said actuating member being rotatable axially to applybraking pressure through said spaced pressure transmitting elements to the cir-. cumi'erentially spaced points or the movable oi said braking parts, and said actuating member bein'g tiltable during its rotation in a plane'parallel to the axis oi the braking parts about a point intermediate the spaced pressure transmitting elements so as to equalize the pressure ape plied through the respective pressure transmitting elements.

15. A braking device comprising a rotary braking element and an opposing non-rotary braking element, one being movable axially into engagefment with the other, a rotatable actuating member. longitudinally spaced elements on said member for'transmitting'braking pressure to circumelements upon rotation oi the member, the actuating member being tiltable about an axis extending transversely of the axis of the brakingelements in" response to the forces, transmltted through the respective spaced-elements to equalize the pressure exerted by respective transmitting elements on the braking elements.

16. A braking device for motor vehicle trans- :missions comprising a rotary braking element, .an opposing non-rotary braking element engage.-

able therewith, spaced elements for transmitting brakingpressure in a direction axially 01. said braking elements to diflerent circumferential areasof one of the braking elements, a rotatable actuating member engageable th the several pressure transmitting elements d operative'to apply pressure simultaneously thereto. and

means for equalizing the pressure applied by the actuating member to the pressure transmitting elements.

' KARL MAYBACH.

- ierentiallyspaced points of the opposing braking 

